7.4 - 9 Electrical connection of the fault signalling
outputs and the signal inputs (image 2 annex)
7.4
Fault signalling outputs
Terminal 1 / 2 / 3 = High water alarm, potential-free, 2 / 3 closed in
case of alarm.
Terminal 4 / 5 / 6 = Overall failure, potential-free, 5 / 6 closed in case
of alarm
Terminal 7 / 8 = Relay output for every failure potential-bound.
In case of an alarm there are 230 V/AC adjacent
(this port is protected by a micro-fuse 1 A T).
7.5
Input for float switch dry run protection
Terminal 10 /11 = Dry run protection
Polarity of the terminals: 10 = positive and 11 = negative (24 V/AC
10 mA)
When a float switch is connected to terminal 10-11, then it can be
prevented that the cutting unit or impeller appears from the
medium. The dry run protection is active in both automatic as well as
manual operation.
For use in the
EX zone
, the corresponding requirements
must be complied with.
This input is optionally also used for locking the unit when a specific
program has been agreed upon.
7.6
Connection examples for the operation of the
switching device with float switches
The display shows which switch is connected. Closing contacts must
always be used.
“Float switch”
must be selected in the menu under
“Level control”
. The input for the high water alarm (terminal 19/20) is
always active.
Operation with a common line of float switches is not possible.
For use in the
EX zone
, the corresponding requirements
must be complied with.
7.7
External level sensor 4 – 20 mA
“4 - 20 mA interface”
must be selected in the menu under
“Level
control”
.
An external sensor 4 - 20 mA two-wire technology (passive
sensor) can be connected to the terminals 25 (-) and 26 (+). The
sensor is supplied with a stabilized direct voltage of approx. 24 volt.
In the delivered state, the measuring range of the level sensor is set
in such a manner that it matches the measuring range of the internal
pressure sensor. In the event that the level sensor should be
connected with a different measuring range, then the corresponding
setting must be changed in the menu (see section 5.2.14). The output
is active, i.e. the sensor is supplied with voltage by the control.
For use in the
EX zone
, the corresponding requirements
must be complied with.
In the event of the connection of an active sensor (external voltage
supply), the positive line of the sensor must be connected to the
negative terminal (25) of the input. The negative line of the sensor
must be connected to the common internal earth (negative),
terminal 28 or 30 (negative of the analogue outputs).
7.8
Analogue outputs
The analogue outputs are intended for the connection to the
control system. The signals change proportionally to the level.
0 - 10 V
= Terminal 27 (+) and 28 (-) resistant up to
max. 10 mA
4 – 20 mA
= Terminal 29 (+) and 30 (-) burden max.
250 ohm
The length of the lines for the analogue outputs must not exceed
1.50 m, and must not be laid along with lines prone to interference.
7.9
Network-independent alarm:
By using a 9V block battery, a mains-independent alarm message can
be issued in the event of a power failure. A continuous acoustic signal
is emitted as an alarm which cannot be acknowledged, even if the
acoustic alarm has been deactivated in the menu.
To deactivate, the
battery must be disconnected.
Please pay attention to the correct polarity when inserting the
battery!
To ensure that it functions properly, the battery must be fully
charged before being inserted or it must be charged in the
switchgear for 24 hours.
Attention!
Under no circumstances should normal
batteries be used.
The following batteries may be used:
Nickel metal hydride accumulator (NiMH)
PS
MEGA
1
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